As you check the connectors already and considering that lifting the tank action seems to "fix" the problem, I say it is mechanical. Something is getting jamed inside maybe
You might also check that red slider on the RHS. You might have knocked it into an "off" position..
You might also check that red slider on the RHS. You might have knocked it into an "off" position..
"It is not a shame to not know, the shame is to not know and not to ask"